The present invention relates to a vibrating apparatus for applying simultaneous multi-directional vibrations to specimens.
In prior art vibrators, a hollow vibration shaft is fixed in a vertical direction with respect to the vibration table with a first exciter for producing vibration in a horizontal direction being coupled to the vibration shaft. A hydrostatic bearing allows slidable movement of the vibration shaft in the horizontal direction. Furthermore, a second exciter is coupled to the lower end of the vibration shaft by a hydrostatic bearing so as to allow slidable movement of the vibration shaft for producing vibration in a vertical direction. Since these two exciters are coupled to a single vibration shaft it has the advantages of being profitable economically and in terms of manufacturing as follows: (1) the apparatus can be miniaturized; (2) the vibration table is easily replaceable; (3) the generation of torsional vibrations such as rolling and pitching are reduced; (4) it is possible to obtain a large acceleration and a high frequency of vibrations; and (5) only a few guiding members are necessary.
The forementioned prior art vibrator is suitable mainly as a vibrator for applying vibration in two dimensions; that is, in the direction parallel to the vibration shaft and in a direction perpendicular to it. Therefore, it is difficult to utilize the above-mentioned vibrator as a two dimensional vibrator which simultaneously vibrates specimens in both of the orthogonal directions perpendicular to the axial direction or as a three dimensional vibrator which simultaneously vibrates specimens in the direction of the axis of the vibration shaft in addition to the other two orthogonal directions mentioned above.
It is an object of the present invention to provide an improved apparatus for vibrating specimens simultaneously in multiple directions by the use of a single vibration shaft.
It is another object of the present invention to provide a vibrator for applying vibrations simultaneously in multiple directions including at least the two orthogonal directions perpendicular to the axial direction of the vibration shaft.
It is still another object of the present invention to provide a highly effective vibrator suitable for applying vibrations to specimens simultaneously in the direction of the axis of a vibration shaft in addition to the other two orthogonal directions.